Electromagnetic pump

ABSTRACT

RECIPROCATING ELECTROMAGNETIC PUMP COMPRISING A PUMP ELEMENT THE ELASTICALLY RETURNED DIAPHRAGM OF WHICH DISPLACES FLUID BETWEEN A SUCTION VALVE AND A DELIVERY VALVE, AN ELECTROMAGNET CORE CONNECTED BY A ROD TO THE SAID DIAPHRAGM TO DEFORM THE LATTER WHEN THE ELECTROMAGNET IS ENERGIZED AND A SWITCH TRIPPED BY THE ROD AT THE END OF THE OPERATIVE STROKE OF THE SAID CORE TO INTERRUPT THE ENERGIZATION OF THE ELECTROMAGNET AND PERMIT THE ELASTIC RETURN OF THE SAID DIAPHRAGM INTO A REST POSITION. THE ROD CONTROLS THE DISPLACEMENTS OF AN ELEMENT ASSOCIATED WITH THE SWITCH AND IS CONNECTED ELASTICALLY TO THE CASING OF THE PUMP SO AS TO BE ABLE TO OCCUPY, BY SUDDEN TRIPPING, TWO STABLE POSITIONS RESPECTIVELY IN THE PERIODS OF END OF FORWARD STROKE AND END OF RETURN STROKE OF THE SAID ROD, THE SAID ELEMENT BEING DISPOSED SO THAT IT CAN PRODUCE THE OPEN CONDITION OF THE SWITCH IN ONE POSITION AND THE CLOSED CONDITION IN THE OTHER POSITION.

Oct 31. 1972l I c.Gu|D1cE| L| 3,701,614

ELECTROMAGNETIC PUMP Filed May 4, 1971 2 Sheets-Sheet l Oli 31 1972 y c. GUIDICELLI 3,101,614

ELEcTnoMAGNETIc' PUMP Filed May 4, 1971 2 Sheets-Sheet 2 United States Patent O 3,701,614 ELECTROMAGNETIC PUMP Charles GuidicellL Bagnolet, France, assigner to Societe Anonyme STOP Filed May 4, 1971, Ser. No. 140,038 Claims priority, application France, May 5, 1970, 7016322 Int. Cl. F04!) 43/04 U.S. Cl. 417--413 3 Claims ABSTRACT F THE DlSCLOSURE Reciprocating electromagnetic pump comprising a pump element the elastically returned diaphragm of which displaces uid between a suction valve and a delivery valve, an electromagnet core connected by a rod to the said diaphragm to detorm the latter when the electromagnet is energized and a switch tripped by the rod at the end of the operative stroke of the said core to interrupt the energization of the electromagnet and permit the elastic return of the said diaphragm into a rest position. The rod controls the displacements of an element associated with the switch and is connected elastically to the casing of the pump so as to be able to occupy, by sudden tripping, two stable positions respectively in the periods of end of forward stroke and end of return stroke of the said rod, the said element being disposed so that it can produce the open condition of the switch in one position and the closed condition in the other position.

The present invention relates to improvements in a reciprocating electromagnetic pump.

Such a reciprocating electromagnetic pump is of the type comprising a pump element the elastically returned diaphragm of which displaces uid between an inlet valve and a delivery valve, an electromagnet core connected by a rod to the said diaphragm for the deformation of the latter when the electromagnet is energised and a switch tripped by the rod at the end of the operative stroke of the said core to interrupt the energization of the electromagnet and permit the elastic return of the said diaphragm into a rest position.

ln known reciprocating pumps with high operating speed and short stroke, the drive rod of the diaphragm acts directly upon the push member of a switch and the stroke of this push member determines and limits the stroke of the drive rod.

This presents a drawback which is avoided in the pump according to the invention, in which it has been sought to increase the stroke lby rendering it independent of that of the switch.

The pump according to the invention is characterised in that the rod controls the displacement of an element associated with the said switch and connected elastically to the casing of the pump so that by sudden tripping it is able to occupy two stable positions respectively in the periods of the end of the forward stroke and the end of the return stroke of the said rod, the said element being disposed so that it causes the open condition of the switch in one position and the closed condition in the other position.

According to another characteristic of the invention the said element consists of a sleeve through which the ICC rod passes and which cooperates with drive stops provided on the latter to thrust the said sleeve respectively p into the one or the other of the said stable positions.

According to yet another characteristic of the invention the sleeve is supported by a suddenly rocking exible blade extending in a plane substantially perpendicularly to the said rod and the ends of which are engaged in notches formed in the casing of the pump.

It will be understood that with the characteristics set forth above the rod comprising the stops entrains the said element only at the ends of the stroke of the core and in this manner the latter acts on the rod while the stop controlling the displacement of the said element causing opening of the electric circuit has not come into abutment with the said element to cause the sudden tripping from which the controlling of the switch results.

The invention will be better understood' on reading of the following description with reference to the accompanying drawings, wherein:

FIG. 1 is an axial sectional view of a pump according to the invention,

FIG. 2 is likewise an axial section of the pump along the line 2 2l in FIG. l,

FIG. 3 is a cross-sectional view along the line 3 3 in FIG. 1 or FIG. 2 and FIG. 4 represents a suddenly triping blade carrying the contact of the pump switch, seen from above.

Referring to the drawing, the electromagnetic pump comprises in a casing 10, a pump element disposed at the base of the said casing and comprising an elastic diaphragm 12 the periphery '114 of which is gripped by an annular piece 16 against a block 18. At its centre the block 18 comprises a blind bore 20 which with the iaphragm 12 deiines a chamber 22 connected by conduits 24- and 26 to tubes 28 and 30 for admission and delivery respectively, suitable valves 32 and 34 being interposed between the tube 28 and the conduit 24 on the one hand and between the tube 30 and the conduit 26 on the other.

The pump which has just been described is of a type which is conventional in the iield of manually controlled screen washers. Such a pump is of the suction and forcepump type. In the drawing the diaphragm 12 is in the rest position, that is to say at the end of a suction cycle. The position normally occupied by the diaphragm 12 at the end of a delivery cycle is represented in broken lines in FIG. 2.

At the top of FIGS. 1 and 2 there is represented the electromagnetic drive of the pump which has just been described. At 40 there is shown the coil of an electromagnet the body of which is constituted by a U-piece 42, a closure plate 44 and a central tubular element 46 which extends into a tubular casing i48 constituting the body of the coil 40. The casing 48' is closed by a lid 50* against the internal face of which there is stuck an elastic foam washer 52. In the tube `48 between the foam block 52 and the magnetic piece 46 there is slidingly mounted a soft iron magnetic core 54 which is normally thrust elastically towards the washer 52 by a rod 56 the upper end of which abuts against the lower face of the core S4 and the lower frusto-conical end of which is centred in a similarly frusto-conical cavity of the diaphragm 12. At its upper end the rod 56 comprises a part '58` of larger diameter dening a shoulder 60y and at its lower part has a flange 162. In this way the rod 56 is guided by the 3 part 58 in the tube 46 and by its fHange 62 against the wall 64 of the casing 10.

In the tubular element 46, coaxially with the rod 56, a tubular element forming a sleeve 66 is slidingly mounted which has at its central part an annular flange 68 sliding in a part of larger diameter of the tube 46 and capable of coming into abutment 4against the shoulder 70 thus defined in the tube 46. At its upper part the sleeve-forming element 66 has a radial internal flange 72 the internal diameter of which is less than the diameter of the part 58 of the rod 56, so that the said flange 72 constitutes a projection against which the shoulder 60 of the part 58 of the rod 56 can come into abutment in order to drive the sleeve 66 slidingly in a downward movement of the rod 56. At its lower part the sleeve 66 bears through a collar 74 against the flange 62 of the rod 56. The dimensions of the various elements as just described in the axial direction are such that, in the rest position as represented in FIG. l, the diaphragm 12 elastically thrusts the flange 68 of the sleeve 66 against the shoulder 70 of the tube 46 through the intermediary of the ilange 62 of the rod 56 and that a clearance A exists between the shoulder 60 of the rod 56 and the internal flange 72 of the sleeve 66.

At the lower part of the sleeve 66 two rectangular ports 76 are cut out the axes of symmetry of which in the axial direction are substantially in the sectional plane of FIG. l. These ports extend axially over a distance slightly leSs than that between the central flange 68 of the sleeve 66 and the collar 74 situated at the lower end of the latter. In the ports 76 there are lodged rectangular blades 78 of elastic metal, for example spring steel. The blades 78 have a length slightly greater than that of the ports 76 and a width slightly less than that of the said ports, so that they are capable of exing, as shown in the drawing, towards the interior of these ports.

The central part of the blades 78 is connected to an elastic suddenly tripped blade designated as a whole by the reference 80, which will now be described with more particular reference to FIG. 4.

The lblade 80 is in the form of a rectangular elongated frame having two major sides 82 conected on the one hand by a blade part forming a heel 84 engaged in a transverse slot 86 formed in an insulating block forming part of the casing 10. The heel 84 is on the one part prolonged by an electric connection tongue 87 and on the other towards the interior of the frame by a projecting blade portion 88 the free end of which is articulated to the central part of one of the two blades 78. The end of the blade 80 opposite to the heel 84 comprises a contact bead 90 disposed -in a notch 92 formed in an insulating material part of the casing and having on its lower face a contact 94 capable of electrically cooperating with the contact 90. The end part of the blade 80 carrying the contact bead 90 is prolonged towards the interior of the frame by a blade portion 95 extending parallel with the edge 82 to come into articulated cooperation with the other blade 78.

The contact bead 94 is carried -by a conductive material bar 96 which projects from the casing as shown in FIGS. 2 and 3 to be connected with the electric supply circuit.

On the left in FIG. 1 the connection between the other connection terminal 98 (FIG. 3) and an input of the electromagnet coil 40 and the connection between the tongue 87 of the blade 80 and the output of the electromagnet are` represented diagrammatically by means of dot-and-dash lines.

The manner of operation of the pump which has just been described is as follows:

As represented in FIG. 1, the pump is in the rest position following a suction phase. The chamber 22 is normally filled with liquid to be transmitted and the diaphragm 12 elastically thrusts the rod 56 and the core 54 into the upward position. The flange 62 of the rod 56 holds the sleeve 66 likewise in the upward position in abut- Vthe terminal 98. The electromagnet being energised, the

core 54 is slidingly lowered into the internal tubular part of the coil 48, it thrusts upon the head 58 of the rod 56 the lower end of which acts downwards, considered in the drawing, upon the diaphragm 12 to expel the liquid contained in the chamber 22 through the outlet valve 34.

The core S4 displaces the rod 56 vertically downwards, considered in the drawing, which rod progressively deforms the diaphragm 12. The shoulder 60 approaches the internal radial flange 72 of the sleeve 66 and the latter moves with the rod 56 once the clearance A has been taken up. As the rod 56 and the sleeve 66 then move simultaneously by a stroke corresponding to the sudden tripping of the blade 80, which has the effect of causing the suddent disengagement of the bead 19 of the blade in departure from the bead 94 connected to the terminal 96. This then corresponds to the end of the delivery phase and the diaphragm 12 occupies the position represented in broken lines in FIG. 2.

As the electric current has been interrupted by separation of the beads and 94, the rod 56 re-ascends, pushing back the core 54 merely under the elastic effect of the diaphragm 12 which in its re-ascent eifects the suction into the chamber 22 of fluid coming from the tube 28 and the valve 32, the delivery valve 34 being closed and applied against its seating provided at the end of the conduit 26. On re-ascent of the rod 56, its flange 62 approaches the collar 74 of the sleeve 66 and after a sudden reascent comes into abutment against the latter to return it -into the position which it occupies in FIG. 1. After a short stroke following the abutment of the tlange 62 upon the collar 74, the blade 80 is tripped and the bead 90 which was abutting upon the upper part of the notch 92 is forcefully returned to the head 94. This then corresponds tothe end of the suction cycle and a fresh delivery cycle commences if the switch provided in the supply circuit of the pump has remained closed.

As can be seen from reading of the above description of operation, the apparatus according to the invention possesses no bistable push member the drawbacks of which were specied above, it permits of preserving the magnetic impulse throughout the length of the working stroke of the piston in the delivery of the fluid.

I claim:

1. A reciprocating electromagnetic pump of the type comprising a casing and a pump element having an elastically returned diaphragm which displaces luid between a suction valve and a delivery valve, an electromagnet core having a rod connected to the said diaphragm to deform the latter when the electromagnet is energized and a switch tripped by the rod at the end 0f the operative stroke of the sa-id core to interrupt the energization of the electromagnet and permit the elastic return of the said diaphragm into a rest position, characterized by .an element movable by said rod, said element being associated with the said switch and connected elastically to the casing of the pump so as to be able to occupy, by sudden tripping, two stable positions respectively in the periods of end of forward stroke and end of return stroke of the said rod, the said element being disposed so that it can produce the open condition of the switch in one position and the closed condition in the other position, said element consisting of a sleeve through which the rod passes, said rod provided with drive stops to thrust the said sleeve respectively into the one or the other of the said stable positions, said sleeve being supported by a suddenly rocking flexible blade extending in a plane substantially perpendicular to the said rod and the ends of which are engaged in notches formed in the casing of the pump.

2. A pump according to claim 1, characterized in that the exible blade is made of an electrically conductive material, one of the said notches carrying an electric contact which, in combination with the blade, constitutes the said switch.

3. A pump according to claim 2, characterized in that the sleeve passes through the blade in its central part, the sleeve-blade connection being effected through the intermediary of longitudinal elastic plates disposed diametrically oppositely on the sleeve so as to ex radially in the sudden rocking of the said blade.

References Cited UNITED STATES PATENTS 10 WILLIAM L. FREEH, Primary Examiner J. T. WINBURN, Assistant Examiner 

